الفهرس 
دراسات فيزيقية وكيميائية وتكنولوجية علي بذور الشيا كمصدر جديد وواعد اللغذاءOnly 14 pages are availabe for public view
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Abstract
The work in this study concerned to evaluate the quality of the produced local chia seed comparing with imported or imported one and to use whole, ground, oil, rich protein and rich fibers defatted flour fractions in addition to mucilage of chia seed in preparing different types of an acceptable new functional food products.
A- Whole chia seed:
1. Physical properties and weight composition:
1.1. Both local and imported chia seeds were very small in size and had a dark color. The shape of both local and imported chia seeds can be described oval or pear like. The local chia seed had slightly higher length, width, relatively smaller seed index, thickness and bulk density than imported one.
1.2. Local chia seed had higher values of lightness (L*), redness (a*) and yellowness (b*) than imported one. Therefore, the color of local seeds can be described as a deep gray or beige with small dark spots. Meanwhile the imported seeds had a black or deep dark yellow color similar to that of dark coffee.
1.3. The hull percentage represented up to 50% of the weight composition of chia seeds. It was higher in imported seeds than local ones. Chia seed kernel ranged from 44.4 to 49%. It was higher in local chia seed than imported one.
2. Proximate composition and caloric value:
2.1. The moisture content of chia seeds was low (7.3 to 7.8%). Dry matter of both local and imported chia seeds was up to 90%.
2.2. The lipids, proteins, ash, crude fibers and nitrogen free extracts ranged from 36.57 to 37.2, 26.1 to 27.89, 4.8 to 5.15, 22.22 to 24.31 and 5.8 to 9.96%, respectively in both local and imported chia seeds. The content of lipids, proteins and crude fibers was relatively higher, ash and nitrogen free extracts was slightly lower in imported than local chia seeds.
2.3.Both local and imported chia seed, had nearly similar caloric value (562.25 to 566.8 k.cal/100g).
3. Mineral content: The whole chia seed had high levels of phosphorus (769-814 mg/100g), calcium (574-592 mg/100g), potassium (323.79-535 mg/100g), magnesium (287.4-296 mg/100g) and low values of sodium (25.5 to 34.7 mg/100g), iron (5.39 to 7.1 mg /100g), zinc (3.76 to 5.19 mg/100g), manganese (1.55-1.65 mg/100g) and copper (0.748 to 0.936 mg/100g). Imported chia seed had higher values of potassium, phosphorus, copper, lower amount of sodium, calcium, zinc, manganese, magnesium and iron than local ones. The ratio between calcium to phosphorus was 0.75 in local and 0.70 in imported chia seeds.
B- Chia seed oil:
1. Classes: The oil of both local and imported chia seeds was fractionated into clear seven classes. These classes were, from origin to front, mono glycerides, 1,2 (or 2,3) diglycerides, free sterols, 1,3 diglycerides, free fatty acids, triglycerides and sterol esters and other hydrocarbons. Triglyceride represents the main components of both local and imported chia seed oils.
2. Triglycerides: Generally, triglycerides of local and imported chia seed oil were fractionated into identical seven groups. group with 9 double bond found in highest intensity followed by group 2 (with 8 double bonds), 3 (with 7 double bonds), 4 (with 6 double bonds), 5 (with 5 double bonds), 6 (with 4 double
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bonds), and 7 (with 3 double bonds), respectively. This means that chia seed oil is high in polyunsaturated fatty acids
3. Fatty acid composition: Up to 80% of fatty acid composition of chia seed oil was polyunsaturated fatty acids. Both ω3 linolenic acid (62.93-64.56%) and ω6 linoleic acid (16.77-20.67%) were the major components of chia seed oil. This oil also contained oleic acid (6.03-6.35%), palmitic acid (6.3-7.15%), stearic acid (1.31-1.78%) and traces of other saturated fatty acid. Slight differences were noticed in fatty acid composition between both local and imported chia seed oil. The mean of ratio between saturated to unsaturated fatty acids and ω6 fatty acid to ω3 one was 1: 9.5 and 1: 3.5, respectively.
4. Identity characteristics: The chia seed oil had a light amber color and clear appearance. The relative density, iodine value and saponification index ranged from 0.9239 to 0.9241 at 20°C, 194.7 to 198.4 gI2/100g oil and 189.1 to 191.3 mg KOH/g oil in chia oil of both local and imported seeds.
C- Defatted chia seed flour:
1. Proximate composition: Protein, ash, crude fibers and nitrogen free extract were increased from 26.1 to 41.14, 5.15 to 8.27, 22.22 to 35.03 and 9.96 to 15.56%, respectively in local, from 27.89 to 44.41, 4.8 to 7.64, 24.31 to 38.86 and 5.8 to 9.09%, respectively in imported chia seeds after oil extraction. Both protein and crude fibers are the main components of defatted chia seeds.
2. Dietary fibers and mucilage: Defatted chia seed flour contained high level of total dietary fiber, 57.7% in local and 55.8% in imported one. It was composed of 92.37 and 86.38% insoluble dietary fiber (IDF), 7.63 and 13.62% soluble dietary fiber (SDF) in local and imported defatted chia seed flour, respectively. The IDF to SDF ratio is nearly 12.11:1 and 6.34:1 in defatted local and imported defatted chia seeds, respectively. Chia seed free fat flour contained high amount of neutral detergent fiber (NDF), 63-67.2% and low level of acid detergent fiber (ADF), 34-36%. Local and imported defatted chia seeds flour had 6.23 and 7.4% mucilage content, respectively.
3. Total phenolic content as mg/g as gallic acid equivalent, was higher in local (1.42 mg/g) than imported (1.1 mg/g) chia seed defatted flour.
4. Identification and quantification of phenolic compounds by HPLC showed 19 ones. These compounds can be arranged according to their concentrations (ug/g) in the following decreasing order, caffeic acid, gentisic, rosmarinic, cteachin, rutin, ferulic acid, gallic acid, vanillic acid, cinnamic acid, Ρ-hydroxybenzoic acid, apigenin, Ρ-coumaric acid, apigenin-7-glucoside, chrysin, sinapic acid, syringic acid, kaempferol, quercetin and protocatechuic acid, respectively. These compounds were found in defatted flour of both local and imported chia seeds. Most of these compounds found at slight higher levels in imported seed than local ones.
5. Antioxidant activity measured by two different methods, namely DPPH and ABTS. Generally, the antioxidant activity of the defatted local chia seed ethanolic extract was relatively higher by the previous two mentioned methods than imported one.
6. Functional properties: Both local and imported chia seed defatted flour are able to hold high amount of water and oil. Their emulsification capacities were up to 50 ml/100ml. Foaming capacity of chia seed defatted flour was low 18-20% in local and imported seeds. The foam stability was decreased slowly upon standing at room temperature until 60 min.